Blog post by Jean-Olivier Irisson
Blog post by Jean-Olivier Irisson
Hey plankton hunters! Welcome to our 3rd round of Fantastic Find Friday here at Plankton Portal. There have been so many awesome finds on the site and we picked 5 this week for you to check out. If you see something really neat on the portal than tag it with #FFF so we can check it out for use on the blog. Here we go!
Physonect Siphonophore— #Sipho #Corncob
This is a stunning capture of a physonect siphonophore who seems to be waving hello to ISIIS as she passes by. Like all siphonophores, this guy here is a colonial organism comprised of many individual animals or ‘zooids.’ Each zooid is specialized and distinct, but work together so closely that they more resemble a single organism than a colony of animals. On display here are the branching tentacles used for foraging and the swimming bells that resemble a corncob. This one is a stunner!
Lobate Ctenophore — #Lobate
This is a really neat capture of a lobate ctenophore (Ocyropsis maculata), showing off the feature that gives this guy his name. In this image you can see clearly the internal structure and the striated texture of his muscular, gelatinous body. Lobate ctenophores swim lobes forwards by beating the ciliated comb rows situated on the opposite (aboral) end. The one depicted here would be swimming towards us and to the left. I wonder if larvacean is on the menu?
Chaetognath — #Arrowworm
Looks like an arrow shot by some undersea archer, right? Arrow worms, or chaetognaths, are carnivorous marine worms belonging to the Phylum Chaetognatha. They are notoriously ferocious predators that hunt other plankton with the help of hooked ‘grasping spines’ that flank the mouth. Chaetognaths have fins for propulsion and steering—you can see all of them really well in this capture! While these fins superficially resemble those of a fish, they are not related evolutionary and are structurally very different.
Calycophoran Siphonophore — #Rocketship #Triangle
I bet NASA would get a lot more funding if they built space shuttles that looked like this! This beautiful capture of a siphonophore really looks to me like some sci-fi monster a (horrified) astronomer might see in a telescope! Don’t worry though, this guy is just a couple of cm’s long and probably couldn’t hurt you if he tried. Just like the physonect siphonophore above, this guy is a colonial organism and would therefore be more appropriately referred to as guys. The tail, or stem, on display here contains two developmental stages of siphonophore simultaneously—both the medusa and polyp stages. Unlike most cnidarians that alternate between these stages generationally, this guy chooses to have them coexist within the same colony. If you look closely you can see them bickering over who is the prettiest!
Calanoid Copepod — #Copepod
This copepod is making a heart with his antennae! Do you think he might be in love? There is some 13,000 species of copepod in the world and they are a crucial component of plankton communities and global ecology in general. It has been suggested that copepods may comprise the largest animal biomass on the planet! Many species of marine life, large and small, rely on these guys as their main food source, including whales and seabirds. Looks like this guy here is a lover not a fighter!
Looking forward to next time !
In many fields of science, new technology is leading to unprecedented data production. This, in turn, requires extensive analysis with minimal sub-sampling to detect as much detail as possible. In biological oceanography, imaging systems have become more useful with increasing computer speed and storage capabilities, and image data address some of the fundamental problems with traditional sampling methods that are destructive to fragile organisms (i.e., jellyfish and marine snow). On a given tow with our system, the In Situ Ichthyoplankton Imaging System (ISIIS), we produce approximately 400,000 images in 7 hours with many different species across a range of sizes present in each image (500 μm to 13 cm). This is an incredible amount of information that would take years for one person to fully analyze. When we are out at sea, we typically sample for WEEKS and come back to land with millions of images. Computer algorithms can perform basic tasks of extracting specimens that look similar, but human brains are extremely adept at interpreting an organism in 3D and providing context in the image data that a computer cannot. The amazing abilities of people to recognize patterns that computer algorithms may see as unimportant cannot be underestimated.
Another reason we are using Citizen Science is so that you, the citizen scientist, can participate in the process of discovery. After all, most oceanographic research is funded at least in part by taxpayer money, and these novel plankton images combined with Citizen Science are a great way to engage those who fund the research. We think it is far more effective to cultivate interest in science through the discovery process itself, rather than the production of jargon-filled reports and papers only understood by other oceanographers (don’t worry, those will come later). In addition, this online format provides an opportunity for us to educate people about life in the oceans, potentially inspiring the next generation of ocean scientists. With Citizen Science, there is the potential for new discoveries arising from simply allowing many people to look at the images.
We believe our research with ISIIS is particularly applicable to Citizen Science and the process of discovery because this new imaging technology provides a huge amount of data and a unique glimpse into ocean life. I have spent the last 5 years of my graduate school career at the University of Miami examining hundreds of thousands of plankton images, and every time I flip through the images, I always have the feeling that I could see something that no human has ever seen before. I try to instill this sense of wonder and hope for discovery in all people that work with the images, because when you see something interesting, like an elaborate siphonophore or a dense patch of copepods, you are likely the first person to see that species in its natural environment. When we get enough eyes on these images and discussions facilitated through the Plankton Portal website, the sky’s the limit for the discoveries that can be made with Citizen Science!
Since the 1800’s, plankton has been studied and collected using simple nets with very fine mesh. The process of analysis of these plankton ‘samples’ is tedious, labor intensive, confined to laboratory, and can only be done on relatively small areas of the ocean. By sampling in this manner, it is difficult to get a good understanding of how planktonic organisms are distributed and how they interact with each other. Yet plankton represents a very important part of a global system feeding larger animals like fish, whales and many others. The In Situ Ichthyoplankton Imaging System (ISIIS) is one of a few systems in the world capable of improving the way we study plankton to better understand their life and function in the marine environment. Instead of using an actual net to capture plankton, ISIIS captures the images of the organisms and information about their immediate surroundings. ISIIS samples continuously, resulting in a collection of digital images that record the exact location of the various plankton organisms in relation to each other and the environment in which they live. Further, the images are recorded onto a simple hard drive instead of slurry of plankton all mixed together in a sample jar with formaldehyde (yech!).
ISIIS is an underwater imaging system developed to capture real time images of plankton that are relatively rare, small, and fragile such as fish larvae and delicate gelatinous organisms (like jelly fish). ISIIS is composed not only of a macro-camera system with its own illumination but it also is integrated into an underwater vehicle with a variety of additional sensors to measure the depth, salinity and temperature of the water, as well as such properties as dissolved oxygen, light level, and even how much chlorophyll a (measure of primary production) is present. Together, the camera and sensors provide detailed profiles and tracks of what plankton are where and what the ocean environment around them is like.
The vehicle, and associated imaging system and sensors, moves up and down through the water column using side-mounted, user-controlled dive fins (like an underwater glider) while being towed behind an oceanographic ship moving at 5 knots. The vehicle frame is divided into four compartmentalized enclosures with imaging and optical equipment seamlessly integrated into ISIIS’s ventral housings and environmental sensors and electronics in the dorsal housings. ISIIS is designed to undulate in a zigzag fashion between the surface and a maximum depth of 200 meters.
The ISIIS system utilizes imaging technology very similar to an office scanner flipped on its side. The imaged parcel of water passes between the forward portions of two streamlined pods where it is “scanned” and transformed into a continuous image. The resulting very high-resolution image is of plankton in their natural position and orientation. When a sufficient volume of water is imaged this way, quantification of concentration (individuals per unit volume) and fine scale distribution is possible. ISIIS is capable of imaging a maximum of 162 Liters (43 gallons) of water per second (when moving at 5 knots) with a pixel resolution of 70 µm (the thickness of a human hair).
The imaging data and associated oceanographic data are sent to the surface ship via a fiber optic cable and recorder onto a main computer for later viewing and analysis.